OD light flashing

[knt51608]

ok Ive checked the FIPL voltage its set at a dead-on 1.1V. WOT is 3.83V. Have watched voltage sweep from closed throttle all the way to WOT doing slow movements and fast movements checking for spikes or glithces....and have found none. I understand that this problem could also be caused by a tach sendeing unit not functioning correctly....I tried to pull data on the truck with my snap-on Modus Diagnotstics but not available on an 89' F350. I noticed today while looking at the tach sender that there is oil seeping out from around the wires could this be causing the problem im incurring any help will be greatly appreciated...especially since i just layed out $1600.00 to rebuild the E4OD tranny

 

[NJKen]

If anything, pull the tach sensor and clean it up. Does the tach work reliably? With out geting the trouble code its hard to lay blame on anything. It could be a fault with the MLPS (switch on tranny, has upgrades avaialable), It could be the rear end speed sensor, the tach sensor, the TCM relay, wiring, etc......
Ken

 

[knt51608]

th guiage inside works then itll glitch act crazy for a few moments jumping around then act fine again. I'll pull it today and cleanit to see if that helps. the ECM does have the updates and the trannyt has the new upgraded vavle body. Just tryin to get it reliable enough so i feel comfortable with my wife driving it an knowing shes not going to have any major problems while hauling horses to a show

 

[R.w]

i just picked up a 94 crew cab and my OD light flashes every once in a while and my tack is all over the place . The trans was supposdly rebuilt within the last 10,000 miles. Where is the tach sender ?

 

[pafixitman]

Jumping tach is a bad tach sensor. The sensor is the 1" nut to the right of the oil fill with 2 wires coming out of it.

I have cleaned them and had them work for a few weeks but replacement is best.